Effect of salt solution composition on moisture release curves of soil

Soil Research ◽  
1979 ◽  
Vol 17 (1) ◽  
pp. 89 ◽  
Author(s):  
NS Jayawardane ◽  
JA Beattie
Keyword(s):  
Pore Size ◽  
Salt Solution ◽  
Electrolyte Concentration ◽  
Sodium Absorption ◽  
Alluvial Soils ◽  
Salt Solutions ◽  
Solution Composition ◽  
Sodium Absorption Ratio ◽  
Wide Range ◽  
Size Index

A pore size index was used to express quantitatively the relative decrease in size of common pore of confined columns of krasnozem, red-brown and alluvial soils, with reduction in electrolyte concentration of percolating solutions of a given sodium absorption ratio (SAR). The pore size index of red-brown and alluvial soils decreased markedly with reduction in electrolyte concentration, especially in solutions of high SAR. In the krasnozem soil the pore size index remained fairly constant for a wide range of salt solutions. Moisture release curves of red-brown soil for solutions of decreasing electrolyte concentration and constant SAR and for solutions of increasing SAR and constant electrolyte concentration can be used in combination to obtain moisture release curves of this soil for solutions at any intermediate values of SAR and electrolyte concentration. They also reveal the pattern of volume change of different sized pores.

An equivalent salt solutions method for predicting hydraulic conductivities of soils for different salt solutions

Soil Research ◽  
1979 ◽  
Vol 17 (3) ◽  
pp. 423 ◽  
Author(s):  
NS Jayawardane
Keyword(s):  
Boundary Conditions ◽  
Salt Solution ◽  
Electrolyte Concentration ◽  
Alluvial Soil ◽  
Sodium Absorption ◽  
Pore Geometry ◽  
Specific Pressure ◽  
Salt Solutions ◽  
Sodium Absorption Ratio ◽  
The Relationship

Equivalent salt solutions are defined as solutions with combinations of sodium absorption ratio (SAR) and electrolyte concentration producing the same extent of clay swelling in a given soil. It is suggested that in the presence of different equivalent salt solutions a given soil will have the same pore geometry, the same saturated and unsaturated conductivities at specific pressure heads, and hence the same capacity to transmit such solutions under specific boundary conditions. This concept of equivalent salt solutions was used to develop a method for predicting the saturated hydraulic conductivities of soils for different salt solutions. The basic data required for such predictions in a given soil are the equivalent salt solution values and the relationship between saturated conductivity and electrolyte concentration at a given SAR. Saturated conductivities of a red-brown soil and an alluvial soil for salt solutions of SAR 20 and 10 and different electrolyte concentrations predicted by this method were fairly close to measured values. The significance of this concept to field problems involving flow of the salt solutions through soils is briefly discussed.

Further examination of the use of the equivalent salt solutions method for predicting hydraulic conductivity of soils for different salt solutions

Soil Research ◽  
1983 ◽  
Vol 21 (1) ◽  
pp. 105 ◽  
Author(s):  
NS Jayawardane
Keyword(s):  
Hydraulic Conductivity ◽  
Satisfactory Agreement ◽  
Salt Solution ◽  
Solution Method ◽  
Domain Model ◽  
Sodium Absorption ◽  
Salt Solutions ◽  
Sodium Absorption Ratio ◽  
Model Method ◽  
Solution Methods

Hydraulic conductivities of Pachappa and Waukena soils for different salt solutions, predicted by the equivalent salt solution methods, showed satisfactory agreement with measured values. The values of equivalent salt solutions for these soils were calculated from macroscopic swelling values of extracted clays. The equivalent salt solution method and the simplified domain model method of McNeal predicted equally accurately, the changes in hydraulic conductivities of Pachappa soil in salt solutions with sodium absorption ratio values from 15 to 100.

Prediction of unsaturated hydraulic conductivity changes of a loamy soil in different salt solutions by using the equivalent salt solutions concept

Soil Research ◽  
1992 ◽  
Vol 30 (5) ◽  
pp. 565 ◽  
Author(s):  
NS Jayawardane
Keyword(s):  
Hydraulic Conductivity ◽  
Salt Solution ◽  
Electrolyte Concentration ◽  
Saline Water ◽  
Saturated Hydraulic Conductivity ◽  
Sodium Absorption ◽  
Published Data ◽  
Salt Solutions ◽  
Solution Series ◽  
Water Contents

Equivalent salt solutions series have been previously defined as solutions with combinations of sodium absorption ratio (SAR) and electrolyte concentration (E,) producing the same extent of clay swelling in a given soil. These equivalent salt solutions series values have yielded satisfactory predictions of changes in saturated hydraulic conductivity, with changes in salt solution composition and concentrations. In the present study, previously published data on changes in saturated and unsaturated hydraulic conductivities of Gilat soil in salt solutions of cationic ratio 0-50 (mmol dm-3)1/2 and electrolyte concentration 2-50 (m.e. dm-3) were used to compare the equivalent salt solution series values for hydraulic conductivities at different water contents. The equivalent salt solution series causing a given change in saturated hydraulic conductivity of a loamy Gilat soil were derived. These equivalent salt solution values were used to predict the unsaturated hydraulic conductivities of this soil at low water contents. Predictions of unsaturated conductivity at relative water contents (�) ranging from 0.80 to 0.20 agreed closely with the measured values. Coefficients log a1 and b1 for Gilat soil, in the equation log Ec = log a1+b1 log SAR, relating the Ec and SAR values of each equivalent salt solutions series were determined at � values between 1.00 and 0.20. The relationship between log a1 and bl was similar at all water contents, in agreement with the equivalent salt solutions concept. Therefore, equivalent salt solution parameters derived from saturated hydraulic conductivity measurements could be used to predict changes in unsaturated conductivities and hence flow rates of saline water under specified boundary conditions.

Study on the influence on the formation of highly ordered porous anodic aluminia membrane

2017 ◽  
Author(s):  
O Pong-Sik ◽  
Ryang Se-Hun ◽  
Sin Gum-Chol ◽  
Hwang Guk-Nam ◽  
yongson hong
Keyword(s):  
Pore Diameter ◽  
Electrolyte Concentration ◽  
Aao Template ◽  
Alumina Template ◽  
Wide Range ◽  
Electrochemical Mechanism ◽  
Porous Anodic Alumina Template ◽  
Ordered Porous ◽  
Anodic Alumina Template ◽  
Scanning Electron

We have studied porous anodic alumina template through the second anodic oxidation of preparation. Observing the morphology of nanoscale AAO template using scanning electron microscope (SEM), the results indicate that the pores are orderly paralleled arranged with uniform pore diameter, perpendicular to the template surface. A detailed study of the influence of different oxidation conditions, such as different type of electrolyte, concentration, voltage and temperature on the template of alumina and its electrochemical mechanism were performed. By changing the oxidation voltage, electrolyte type, concentration, pore diameter and template thickness can be altered in a wide range such that we can obtain the desired aspect ratio. <br>

Application of the ceramic membrane with hydrophobic skin layer to separation of activated sludge

1997 ◽  
Vol 35 (8) ◽  
pp. 137-144 ◽  
Author(s):  
Tsuyoshi Nomura ◽  
Takao Fujii ◽  
Motoyuki Suzuki
Keyword(s):  
Activated Sludge ◽  
Pore Size ◽  
Ceramic Membrane ◽  
Membrane Separation ◽  
Porous Ceramic ◽  
Porous Membrane ◽  
Skin Layer ◽  
Gas Permeation ◽  
Wide Range ◽  
Cake Layer

Porous membrane of poly(tetrafluoroethylene) (PTFE) was formed on the surface of porous ceramic tubes by means of heat treatment of the PTFE particles deposit layer prepared by filtering PTFE microparticles emulsified in aqueous phase. By means of inert gas permeation, pore size was determined and compared with scanning electron micrograph observation. Also rejection measurement of aqueous dextran solutions of wide range of molecular weights showed consistent results regarding the pore size. Since the membrane prepared by this method is stable and has unique features derived from PTFE, it is expected that the membrane has interesting applications in the field of water treatment. Membrane separation of activated sludge by this composite membrane and original ceramics membrane showed that the PTFE membrane gives better detachability of the cake layer formed on the membrane. This might be due to the hydrophobic nature of the PTFE skin layer.

scholarly journals Classification of groundwater suitability for irrigation purposes using a comprehensive approach based on the AHP and GIS techniques in North Kurdufan Province, Sudan

2021 ◽  
Vol 11 (7) ◽  
Author(s):  
Elsiddig Eldaw ◽  
Tao Huang ◽  
Adam Khalifa Mohamed ◽  
Yahaya Mahama
Keyword(s):  
Water Quality ◽  
Spatial Distribution ◽  
Groundwater Quality ◽  
Irrigation Water ◽  
Research Effort ◽  
Sodium Absorption ◽  
Irrigation Water Quality ◽  
Middle Income ◽  
Sodium Absorption Ratio ◽  
Deep Aquifers

AbstractDeterioration of groundwater quality due to drastic human interventions is rising at an alarming rate particularly in lower- and middle-income countries. Yet, limited research effort has been devoted to monitoring and ascertaining groundwater quality. The present study develops a comprehensive irrigation water quality index (IWQI) for rating water quality of shallow and deep aquifers in North Kurdufan province, Sudan. The new approach is developed to overcome the deficiencies of the existing irrigation indices and coming up with a unified decision for classifying water quality for irrigation purposes. Because of these indices like permeability index (PI), sodium absorption ratio (SAR), etc., depending on specific elements, entirely subjective, as well as the great variations in their results, particularly when classifying water quality. Thus, IWQI is created based on eight indices that are generally used to evaluate irrigation water quality, plus three physicochemical parameters have been proven an impact on water quality. The analytic hierarchy process (AHP) is applied to minimize the subjectivity at assign parameter weights under multiple criteria decision analysis tools (MCDA). The spatial distribution of IWQI agrees with the spatial distribution of the most parameters. The results of our approach reveal that the majority of samples are suitable for irrigation uses for both aquifers except few wells in the confined aquifer. Also, noted that there are very variations in the irrigation indices results for classifying water quality. The comparison result showed that the new index robust, fair calculations and has best classifying of water quality.

scholarly journals Hydrochemical assessment of water quality for irrigation: A case study of the wetland complex of Guerbes-Sanhadja, North-East of Algeria

2018 ◽  
Vol 38 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Sihem Hedjal ◽  
Derradji Zouini ◽  
Abdelwaheb Benamara
Keyword(s):  
Water Quality ◽  
Quality Parameters ◽  
Irrigated Agriculture ◽  
Sodium Absorption ◽  
Sodium Absorption Ratio ◽  
North East ◽  
The Status ◽  
Wetland Complex ◽  
Eastern Algeria ◽  
Irrigation Quality

AbstractThe wetland complex of Guerbes-Sanhadja (north-eastern Algeria), has experienced in recent years a certain economic expansion, particularly agricultural, about 47% of the useful agricultural area marked by several varieties of crops ranging from market gardening to speculative crops, requiring large quantities of water for irrigation purposes, however the swampy areas are the main sources used for irrigation purposes in this practice. It is therefore necessary for this water to have physicochemical properties adapted to plants, in particular the absence of salinity. This study was done to evaluate the status of the swamps areas quality and its suitability for irrigated agriculture. To achieve this objective, water samples from ten swamps areas water were collected from Guerbes-Sanhadja in February and June of 2016. The water quality of these swamps was estimated from different water quality parameters such as pH and electrical conductivity (EC), the chemical parameters like Na+, K+, Ca2+, HCO3−, SO42−, Cl−, BOD5, NO3−, NO2−, NH4+ and PO43−. Based on the physico-chemical analyses, irrigation quality parameters like sodium absorption ratio (SAR), percent sodium (% Na), residual sodium carbonate (RSC), permeability index (PI), magnesium hazard (MH) were calculated. The results showed that the overall concentration of nitrate was very high. About 60 percent of the swampy areas had suitable water quality for chloride, and they had a concentration below the permissible limit for crop irrigation. From the Richards diagram, it is observed that most of the samples from the study area fall in the good to permissible classes for irrigation purpose.

scholarly journals Effect of Grain Size on Microscopic Pore Structure and Fractal Characteristics of Carbonate-Based Sand and Silicate-Based Sand

2021 ◽  
Vol 5 (4) ◽  
pp. 152
Author(s):  
Shao-Heng He ◽  
Zhi Ding ◽  
Hai-Bo Hu ◽  
Min Gao
Keyword(s):  
Grain Size ◽  
Fractal Dimension ◽  
Pore Structure ◽  
Pore Size ◽  
Quartz Sand ◽  
Glass Bead ◽  
Fractal Theory ◽  
Calcareous Sand ◽  
Wide Range ◽  
Fractal Characteristics

In this study, a series of nuclear magnetic resonance (NMR) tests was conducted on calcareous sand, quartz sand, and glass bead with a wide range of grain sizes, to understand the effect of grain size on the micro-pore structure and fractal characteristics of the carbonate-based sand and silicate-based sand. The pore size distribution (PSD) of the tested materials were obtained from the NMR T2 spectra, and fractal theory was introduced to describe the fractal properties of PSD. Results demonstrate that grain size has a significant effect on the PSD of carbonate-based sand and silicate-based sand. As grain size increases, the PSD of sands evolves from a binary structure with two peaks to a ternary structure with three peaks. The increase in the grain size can cause a remarkable increase in the maximum pore size. It is also found that the more irregular the particle shape, the better the continuity between the large and medium pores. In addition, grain size has a considerable effect on the fractal dimension of the micro-pore structure. The increase of grain size can lead to a significant increase in the heterogeneity and fractal dimension in PSD for calcareous sand, quartz sand and glass bead.

scholarly journals Data on estimation for sodium absorption ratio: Using artificial neural network and multiple linear regressions

Data in Brief ◽  
2018 ◽  
Vol 20 ◽  
pp. 1462-1467 ◽  
Author(s):  
Majid Radfard ◽  
Hamed Soleimani ◽  
Samira Nabavi ◽  
Bayram Hashemzadeh ◽  
Hesam Akbari ◽  
...  
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Sodium Absorption ◽  
Multiple Linear Regressions ◽  
Sodium Absorption Ratio ◽  
Absorption Ratio ◽  
Artificial Neural ◽  
Linear Regressions
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